选择性激光熔化制备Ti-6Al-4V的亚表面残余应力分析评估

Mishurova Tatiana, Cabeza Sandra, Artzt Katia, Haubrich Jan, Klaus Manuela, Genzel Christoph, Requena Guillermo, Bruno Giovanni

Bundesanstalt für Materialforschung und-prüfung (BAM; Federal Institute for Materials Research and Testing), Unter den Eichen 87, 12205 Berlin, Germany.

Institute of Materials Research, German Aerospace Center (DLR; Deutsches Zentrum für Luft-und Raumfahrt), Linder Höhe, 51147 Cologne, Germany.

Materials (Basel). 2017 Mar 27;10(4):348. doi: 10.3390/ma10040348.

Ti-6Al-4V bridges were additively fabricated by selective laser melting (SLM) under different scanning speed conditions, to compare the effect of process energy density on the residual stress state. Subsurface lattice strain characterization was conducted by means of synchrotron diffraction in energy dispersive mode. High tensile strain gradients were found at the frontal surface for samples in an as-built condition. The geometry of the samples promotes increasing strains towards the pillar of the bridges. We observed that the higher the laser energy density during fabrication, the lower the lattice strains. A relief of lattice strains takes place after heat treatment.

通过选择性激光熔化（SLM）在不同扫描速度条件下增材制造Ti-6Al-4V桥，以比较工艺能量密度对残余应力状态的影响。采用能量色散模式的同步辐射衍射对亚表面晶格应变进行表征。发现增材制造状态下样品的正面存在高拉伸应变梯度。样品的几何形状促使应变朝着桥的支柱方向增加。我们观察到，制造过程中激光能量密度越高，晶格应变越低。热处理后晶格应变得到缓解。